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Temperature cycling tests in various temperature ranges were carried out to investigate the magnetic degradation of the Zn-coated NdFeB magnet. The losses of the surface magnetic field and magnetic flux were well fitted by using an index model. Compared with the lower limit temperature, the upper limit temperature had more obvious effect on the magnetic degradation. Once the upper limit temperature exceeded ≥160 °C, the magnetic degradation mainly occurred during the first cycle, which was different from the gradual decline with an increase in cycle number at a temperature of ≤140 °C. Moreover, the temperature cycling with a maximum upper limit temperature of 180 °C led to a loss of the remanence intensity, while the coercivity remained stable. Microstructure and element distribution analysis revealed that the oxidation of the Zn coating layer during the temperature cycling causes its cracking and an insertion of the oxygen element into the NdFeB substrate. The Nd-, Pr-rich phase at grain boundaries provided diffusion channels for oxygen elements, leading to a surface oxidation of NdFeB grains.

Xuan-Mugua is a Chinese traditional fruit and is mainly preserved by air drying. To explore the effect of temperature on the drying property and quality of the fruits, they were sliced and dried at 60-90 °C. The results indicated that the drying time shortened from 150 to 80 min with the increasing temperature and the minimal time was found at 90 °C. The total phenolic content and antioxidant activity generally decreased by 5.09-18.27% at higher temperature (90 °C) and their maximums respectively appeared at 60 and 80 °C. Compared with the medium temperatures (60 and 70°C), the phenolic profiles changed obviously at higher temperatures (80 and 90 °C), and a transformation of chlorogenic acid was detected; besides, with the increasing temperature, the main phenolics including catechin and chlorogenic acid respectively decreased by 29.3% and 18.4%. Taking the above findings together, 70 °C should be the proper temperature to dry Xuan-Mugua fruits.

A new isoflavone glycoside, named 3’-hydroxytectorigenin-7-O-β-D-xylosyl-(1→6)-β-D-glucopyranoside (1) was isolated from the flowers of Pueraria montana var. lobata (Willd.) Sanjappa & Pradeep. The structure of compound 1 was characterised by HR-ESI-MS and NMR spectroscopic methods. In radical scavenging activity test using 2, 2-diphenyl-1-picrylhydrazyl (DPPH), compound 1 showed moderate activity with IC50 value of 42 ± 4.2 μg/mL.

Huangshan Gongju was extracted with organic solvents (ethanol, methanol and acetone) of different concentrations (0-90%), and the extracts' phenolic content and antioxidant activity, as well as the correlations between them were examined. With the increasing concentration of organic solvent, the total phenolic compound (TPC) increased continuously and met its maximum at 70% acetone, whereas the total flavonoid compound (TFC) and most individual phenolics met their maximums at 70% ethanol. Similar changes occurred to the antioxidant activity, including DPPH and ABTS scavenging activities, and their maximums were respectively found at 50% acetone and 70% ethanol. The antioxidant activity correlated strongly with TPC/TFC (r 0.954, p 0.01) and individual phenolics (r 0.886, p 0.05), and the strongest correlations between them were mainly given by luteolin-7-O-glucoside (r 0.975, p 0.001). These results suggested that high content organic solvent (50-70%) was beneficial to obtain Huangshan Gongju extracts of higher phenolic content and antioxidant activity, and 70% ethanol may be the promising solvent. Besides, phenolics were found to be the main antioxidants of Huangshan Gongju extracts, and flavonoids especially luteolin-7-O-glucoside may play more important roles in the antioxidant activity.

Dioscin has been known for its anti-cancer activity; however, its detailed molecular mechanisms have not been studied so far. Herein, we evaluated the anti-cancer activity of dioscin for proliferation inhibition and apoptosis in HepG2 cancer cells. Initially, dioscin was purified and identified from Polygonatum sibiricum by HPLC, MS, and NMR analysis, respectively. Dioscin inhibited the cell multiplication at IC50 of 8.34 μM, altered the cell morphology, arrested the cell cycle in G2/M phase and led to considerable programmed cell death. Furthermore, it has efficiently promoted the mitochondrial pathway and death receptor pathway. The inhibition of Caspase-8 and Caspase-9 proteins in these pathways abolished the dioscin induced apoptosis significantly; while dioscin inhibited the PI3K/Akt/mTOR pathway. Moreover, dioscin exposure led to enhanced intracellular ROS generation and the mRNA expression of JNK gene which emphasized their involvement in the apoptosis process in HepG2 cells.

Bamboo leaves soups were subjected to in vitro digestion (including separated oral, gastric and small intestinal digestions, and complete digestion containing above three stages), and their phenolics and antioxidant activities were determined. Compared to control groups, total phenolic content (TPC) in treated groups (including undigested and digested groups) increased at gastric digestion stage but decreased at other digestion stages, and the decrease in small intestinal digestion stage (19.97%) was nearly the same with that in complete digestion stage (19.39%). The antioxidant activity in digested groups almost changed accordingly to their TPC but with no significant difference (p 0.05) as compared with undigested groups; similar results were found in four main individual phenolics including cryptochlorogenic acid, chlorogenic acid, neochlorogenic acid and isoorientin, and their contents were negatively correlated to the pH value of digestion buffers (-0.68 r -0.80, p 0.01). These results indicated that the change of phenolic content and antioxidant activity in digested bamboo leaves soups mainly resulted from the pH of digestion buffers rather than digestive enzymes. In addition, the decrease of phenolics may mainly occur at small intestinal digestion stage where the pH value is the highest in the digestive system.

INTRODUCTION: Kinesin-1 motor is a molecular walking machine constructed with amino acids. The understanding of how those structural elements play their mechanical roles is the key to the understanding of kinesin-1 mechanism. METHODS: Using molecular dynamics simulations, we investigate the role of a helix structure, α4 (also called switch-II helix), of kinesin-1’s motor domain in its processive movement along microtubule. RESULTS: Through the analysis of the structure and the interactions between α4 and the surrounding residues in different nucleotide-binding states, we find that, mechanically, this helix functions as a shaft for kinesin-1’s motor-domain rotation and, structurally, it is an amphipathic helix ensuring its shaft functioning. The hydrophobic side of α4 consists strictly of hydrophobic residues, making it behave like a lubricated surface in contact with the core β-sheet of kinesin-1’s motor domain. The opposite hydrophilic side of α4 leans firmly against microtubule with charged residues locating at both ends to facilitate its positioning onto the intra-tubulin groove. CONCLUSIONS: The special structural feature of α4 makes for an effective reduction of the conformational work in kinesin-1’s force generation process.

The fruits of Gardenia jasminoides Ellis are folk medicines in China and their major components are geniposide and water soluble pigment crocins. This study compared the chemical profiles and free radical scavenging activities of two Zhizi species from five provinces of China, including Jiangxi, Anhui, Hunan, Sichuan and Henan. The results showed that Jiangxi Zhizi contained higher levels of volatiles (71.84%), crocins (20.38 mg/g), geniposide (31.36 mg/g) and flavonoids (84.42 μg quercetin/mg) than four other Zhizi fruits; whereas Hunan Zhizi provided higher total phenolics (33.81 μg catechin/mg) and ABTS/DPPH radical scavenging activities. These findings implied that Jiangxi Zhizi would be suitable for extraction of gardenia yellow and geniposide, as well as preparation of essential oil. This information may provide valuable guidance for application of Zhizi fruits to biomedicine industry in China., Food science; Food engineering; Food technology; Food processing; Food analysis; Food composition; Food chemistry; Gardenia jasminoides; Volatiles; Active components; Different regions; Antioxidative activities.

Phenolic acids and flavonoids in bamboo leaves are of great importance for their functional attributes, but they can hardly be separated simultaneously. In this study, zirconia was prepared and applied as a potential absorbent for simultaneous separation of these phenolic compounds. Three phenolic acids (neochlorogenic acid, chlorogenic acid and cryptochlorogenic acid) and two flavonoids (isoorientin and orientin) were isolated at the same time. The influence of bamboo leaves extraction conditions, zirconia calcination temperatures, desorption conditions and absorption/desorption dynamics on the separation were further investigated. When zirconia-400 (calcined at 400 °C) was treated with 70% ethanol extract of bamboo leaves for 40 min followed by desorption with 70% acetic acid solution for 60 min, the recovery of three chlorogenic acids and two flavonoids was about 65%. To conclude, the concise method developed here may provide a new way for simultaneous separation of phenolic acids and flavonoids from various plants.

The closed-extruding fine blanking was developed to form thick plate and low plasticity materials. In this paper, the principle and process of the closed-extruding fine blanking were elaborated. The material flow and the influence of the process parameters on the forming quality were analyzed. At the same time, by means of metallographic observation and analysis of microhardness as well as surface residual stress, the characteristics of the material in the closed-extruding fine-blanking process were investigated.

Methyl protodioscin (MPD) is a steroid saponin which has been well known for its pharmacological properties. Herein, we evaluated the anti-cancer activity of MPD for proliferation inhibition and apoptosis induction in Hela cells. MPD was purified from the rhizoma of Polygonatum sibiricum primarily and identified by HPLC, UPLC-TOF-MS/MS and NMR analysis, respectively. Results showed that MPD repressed cell proliferation at IC50 of 18.49 μM, altered cell morphology, arrested the cell cycle in G2/M phase, facilitated the generation of intracellular ROS and led to cell apoptosis in a concentration-dependent manner. Furthermore, MPD treatment promoted death receptor pathway and mitochondrial pathway efficiently. The inhibition of Caspase-8 and Caspase-9 proteins in these pathways abolished the apoptosis significantly, further demonstrated the mechanism of MPD-induced apoptosis. These findings offer novel information that MPD may be considered as a possible natural anti-cancerous agent in the form of functional foods or medicinal products.

Zirconium phosphate (ZrP) was prepared and employed to separate strictinin-rich tea polyphenol from Chinese green tea extracts. The influences of ZrP calcination temperatures, green tea extraction conditions, and the amounts of ZrP on the isolation of strictinin-rich tea polyphenol were evaluated; the absorption and desorption dynamics of strictinin on ZrP were also determined. Our results revealed that the HPLC content of strictinin increased from 4.96% in 70% ethanol extract of green tea to 58.2% in isolated strictinin-rich tea polyphenol obtained by ZrP-900 (ZrP calcined at 900°C). Furthermore, the suitable time for both strictinin absorption and desorption was 4 hours at 37°C. The method developed here consisted of easy steps such as ZrP absorption, water washing, and 0.4% phosphoric acid solution desorption, which may facilitate the detection and isolation of strictinin from different samples.

Microtubule not only provides the track for kinesin but also modulates kinesin’s mechanochemical cycle. Microtubule binding greatly increases the rates of two chemical steps occurring inside the nucleotide-binding pocket (NBP) of kinesin, i.e., ATP hydrolysis and ADP release. Kinesin neck linker docking (the key force-generation step) is initiated by the motor head rotation induced by ATP binding which needs an anchor provided by microtubule. These functions of microtubule can only be accomplished through interactions with kinesin. Based on the newly obtained crystal structures of kinesin-microtubule complexes, we investigate the interactions between kinesin’s NBP and microtubule using molecular dynamics simulations. We find that the N-3 motif of NBP has direct interactions with a group of negatively charged residues on α-tubulin through Ser235 and Lys237. These specific long-range interactions induce binding of NBP to microtubule at the right position and assist the formation of the indirect interaction between NBP and microtubule. These interactions between N-3 and microtubule have an important anchor effect for kinesin’s motor domain during its rotation with Ser235 as the rotation center, and also play a crucial role in stabilizing the ATP-hydrolysis environment.

Hibernation in the Arctic ground Squirrel (AGS) is a regulated, adaptive response to arctic environmental conditions. Problem statement: Regional brain Blood Flow (rCBF) has been observed to increase dramatically during arousal in hibernators. However, the real time dynamic change in PtO2 during arousal has not been studied, we hypothesized that PtO2 is Interdependent of Tbrain and a key component in the arousal process. Approach: Simultaneous in vivo measurements of PtO2 and brain temperature (Tbrain) in conjunction with oxygen consumption (V02) were conducted in the striatum of non-sedated, non-anesthetized Arctic ground squirrels during spontaneous arousal from hibernation. Results: A dramatic fluctuation of brain tissue oxygen partial pressure (PtO2) is associated with the complex phenomena of spontaneous arousal. In this study, we observed that: (1) a PtO2 elevation precedes changes in Tbrain and V02; (2) PtO2 changes do not correlate with changes in V02 during arousal and (3), endogenous O2 shift from O2 enriched blood to brain in hibernating AGS induces an arousal with the pharmaceutical chemical, efaproxiral (RSR-13). Conclusion: The four turning points of PtO2 appearing at different Tbrain during arousal suggest that changes in PtO2 are Tbrain interdependent and support the concept that arousal from hibernation is complex process invoking different feedbacks.

Dietary fiber are non-digestible constituents of plant cell walls, and comprise a necessary component of diet and its positive connection with human health. Till now, there is no report about the extraction and physicochemical and functional properties of dietary fiber from bamboo shoots. To find the potential applications of dietary fiber from bamboo shoots in food and health products, the effects of chemical, enzymatic methods and particle size distribution on the chemical and structural composition, physicochemical, and functional properties of dietary fibers (DFs) from bamboo shoots were studied. The results showed that BSEDF and BSCDF had higher total DF and higher soluble DF, respectively. The crystalline regions calculated to be higher in latter and both had irregular surfaces and diverse monosaccharide composition. Both fibers showed good functional properties [water retention capacity (WRC) (11.24-15.13g/g), water swelling capacity (WSC) (18.84-28.75 mL/g), oil holding capacity (OAC) (6.71-10.15 g/g), glucose adsorption capacity (GAC) (0.08-6.89 mmol/g) and glucose retardation index (GRI) (3.57-40.92%)]. WRC of BSCDF and BSEDF decreased with the increase in the mesh size (40-200) while, WSC and OAC increased with mesh sizes (40 to 120), followed by decrease above mesh120. Both particle size and extraction methods significantly affected GRI. In conclusion, physico-chemical properties of fibers can be manipulated through treatments (chemical and enzymatic) to improve their overall functionality. Therefore, both BSCDF and BSEDF can find potential applications in food and health products as a functional ingredient in different aspects.

Objective: To study the use of interventional chemotherapy in comprehensive treatment for advanced nasopharyngeal carcinoma. Methods: Interventional chemotherapy with multi-drugs including cisplatin (DDP) 100 mg, 5-fluorouracfl (5-FU) 1000 mg and bleomycin (BLM) 16 mg was used to treat 30 cases with advanced nasopharyngeal carcinoma before radiotherapy. 50 cases that received radiotherapy alone were used as a control group. The methods, time and dose schedule of radiotherapy were similar in the two groups. Results: The primary lesions in 16 cases and the cervical lymph nodes in 12 cases were reduced in size after interventional chemotherapy. Radiation doses of those in complete response in their primary lesion and cervical lymph nodes were lower than that of the control group (P

SUMMARYHeterothermic mammals tolerate severe hypoxia, as well as a variety of central nervous system insults, better than homeothermic mammals. Tolerance to hypoxia may stem from adaptations associated with the ability to survive hibernation and periodic arousal thermogenesis. Here, we review evidence and mechanisms of hypoxia tolerance during hibernation, euthermy and arousal in heterothermic mammals and consider potential mechanisms for regenerative-like processes, such as synaptogenesis, observed within hours of hypoxic stress associated with arousal thermogenesis.